Catalyst for reduction of carbon monoxide

ABSTRACT

1. IN THE SYNTHESIS OF HYDROCARBON BY REACTION OF CARBON MONOXIDE AND HYDROGEN IN THE PRESENCE OF A CATALYST, THE IMPROVEMENT WHICH COMPRISES CONDUCTING SAID REACTION AT A TEMPERATURE OF FROM 250*. THE 400*C. IN THE PRESENCE OF AN ELECTRON DONOR-ACCEPTOR COMPLEX CATALYST CONSISTING ESSENTIALLY OF (A) AN ALKALI METAL, (B) GRAPHITE, AND (C) A CHLORIDE OF A TRANSITION METAL SELCTED FROM THE GROUP CONSISTING OF GROUPS IVB, VB, VIB, VIIB AND VIII OF THE PERIODIC TABLE, AND WHEREIN THE WEIGHT RATIO OF SAID CHLORIDE TO GRAPHITE IS A 0.001-10:1 AND OF SAID ALKALI METAL TO GRAPHITE AND CHLORIDE IS 0.1-10-1.

United States Patent 3,842,121 CATALYST FOR REDUCTION OF CARBON MONOXIDE Masaru Ichikawa, Tokorozawa, Shuichi Naito and Kohei Kawase, Sagamihara, and Kenzi Tamaru, Kamakura, Japan, assignors to Sagami Chemical Research Center, Tokyo, Japan N0 Drawing. Original application Sept. 29, 1971, Ser. No. 184,907, now abandoned. Divided and this application Feb. 20, 1973, Ser. No. 333,720

Claims priority, application Japan, Oct. 2, 1970, 45/ 85,896; Dec. 11, 1970, 45/109,362 Int. Cl. C07c 27/06, 1/04 U.S. Cl. 260-449 R 7 Claims ABSTRACT OF THE DISCLOSURE A catalyst capable of converting carbon monoxide into hydrocarbons is disclosed, said catalyst comprises at least one alkali metal belonging to Group Ia of the Periodic Table, graphite and at least one halide of a transition metal selected from the group consisting of Groups IVB, VB, VIB, VIIB and VIII of the Periodic Table.

This is a division of application Ser. No. 184,907, filed Sept. 29, 1971, and now abandoned.

This invention relates to a catalyst suitable for use in reduction of carbon monoxide. More particularly, this invention relates to a catalyst capable of synthesizing various hydrocarbons from a mixture of hydrogen and carbon monoxide and the catalyst comprises at least one alkali metal, graphite and at least one halide of a transition metal selected from the group consisting of Groups IVB, VB, VIB, VIIB and VIII of the Periodic Table.

In one of the prior art methods a mixture of carbon monoxide and hydrogen is contacted with a catalyst of nickel, cobalt or iron supported on alumina or diatomaceous earth at a temperature of 200 to 300 C. and under a pressure of 100 atmospheric pressure to produce a liquid hydrocarbon (F. Fischer and H. Tropsch, Brennstoff Chem. 7, 97 (1926), and R. B. Anderson, Adv. in Catalysis V, 355 (1933) In this method, it is important to add a basic compound as promoter to the catalyst system in order to enhance the catalytic activity and improve the selectivity to a higher hydrocarbon. However, such catalyst has an inherent disadvantage in that the life of the catalyst depends upon the partial pressure of carbon monoxide and, therefore, critical control of reaction conditions is required.

The catalyst according to this invention is novel and its constituents are entirely different from those of prior art. By use of the catalyst according to this invention, it is possible to carry out the reduction of carbon monoxide at a normal temperature and pressure, and to obtain a C hydrocarbon, such as ethylene and ethane, in high conversion. The catalyst is not adversely affected by oxygen and the sulfur compounds in the synthesis gas and a reduction treatment is not necessary.

The catalyst according to this invention is a complex compound comprising (a) at least one alkali metal belonging to Group Ia of the Periodic Table, (b) at least one halide of a transition metal selected from the group consisting of Groups IVB, VB, VIB, VIIB and VIII of the Periodic Table and (c) graphite. The preferred transition metal halide is the chloride thereof.

This complex compound comprises an alkali metal as an electron donor, graphite as an electron acceptor, which contains a transition metal halide in an appropriate ice amount. Thus, such complex compound is generally called an electron donor-acceptor complex.

The catalyst according to this invention can be produced by means of (1) subjecting a mixture of graphite and a transition metal halide to a heat treatment at a temperature of from about 250 to 500 C. for about 5 to 20 hours to form a graphite-transition metal halide interlayer complex, (2) adding an alkali metal to the interlayer complex and thereafter (3) heating the mixture under reduced pressure, for example less than 10- cm. Hg, preferably less than l0- cm. Hg, or in an inert gas atmosphere such as argon and nitrogen, at a temperature above the melting point of the alkali metal.

In the catalyst, the weight ratio of the transition metal compound to graphite is generally about 0.001-10z1, preferably 0.01-l.0:1, and the weight ratio of alkali metal to graphite-transition metal halide interlayer complex is generally about 0.1-10:1 and preferably 0.5-1.0:1. The graphite employed for preparation of the catalyst can be produced by pyrolysis of a carbon-containing material, such as coal pitch coke and petroleum pitch coke, or a gaseous hydrocarbon such as methane and ethane, and carbon. The preferred graphite is produced by pyrolysis of active carbon.

The catalyst according to this invention shows a remarkable absorption of hydrogen and carbon monoxide. Hence, when a mixture of these gases is contacted with the catalyst there is observed the formation of C -C hydrocarbons, especially C hydrocarbons, such as ethylene and ethane in a high selectivity. Further, it is possible to produce ammonia and hydrocarbons simultaneously from carbon monoxide and air.

If any one or two of (a) an alkali metal, (b) transition metal halide and (c) graphite are employed individually or in combination as catalyst ingredients, the formation of hydrocarbon is extremely low. In contrast, the threecomponent catalyst of this invention is able to increase the formation of hydrocarbon by ten times and the kind and proportion of hydrocarbons produced may vary depending upon the kind of transition metal employed as catalyst ingredient.

The reduction of carbon monoxide using the catalyst according to this invention is generally carried out at a temperature of from room temperature to 500 C., preferably 250 to 400 C. under a reduced to superatmospheric pressure at a space velocity of -20,000 v./v.- hr. through recirculating or passing-through system. The product is entrapped in suitable trapping means, such as a cooler or condenser.

This invention will be further explained in detail by means of examples; however it should be understood that examples are given only for the purpose of illustration and are not intended to limit the scope of this invention.

EXAMPLE 1 In a 300 cc. U-shaped glass reactor, graphite and a transition metal halide were heated at 300 C. in vacuo (10- mm. Hg) to form graphite-transition metal halide interlayer complex, followed by adding metallic potassium and subjecting to heat treatment under the same conditions to form a three-component catalyst of graphitetransition metal halide-potassium. The surface area of the catalyst was measured according to BET method and found to be about 20 mF/g.

A mixture of hydrogen and carbon monoxide was circulated at a rate of 15 cc./min. in the reactor containing the catalyst. Hydrocarbons entrapped in the condenser were subjected to quantitative and qualitative analysis by means of chromatography and infra-red spectroscopy.

When oxygen was present in an amount corresponding to a partial presusre of 10-20 cm. Hg in the synthesis gas, no decrease in catalytic activity was observed.

The reaction conditions and the results are g1ven m Table 1.

TABLE 1 Partial Amount pressure of hydro Proportion of hydrocarbons (molar Catalyst of gas carbons percent) (cm. Hg) Reaction produced Transition metal temp. after 20 Benhalide Graphite K CO Hz 0.) hrs.- (cc.) C1 C3 C3 C4 C5 zene (2 gr.) (2 gr. 10 40 150 1 27 72 1 0 0 FeCh (0.2 gr.) (2 gr.) (2 gr. 1O 40 200 4 26 69 4 1 0 0 10 40 300 26 4 89 4 3 0 0 Buck (0.6 gr.) (2 gr. (2 gr. 10 40 300 17 4 78 10 8 0 0 05013 (0.6 gr.) (2 gr. (2 gr. 10 40 300 32 3 82 8 2 1 1 W01; (0.2 gr.)- (2 gr. (2 gr. 10 40 300 28 2 84 9 2 1 2 M001 (0.2 gr.) (2 gr. (2 gr. 40 300 34 5 87 4 1 1 2 RhCh (0.6 (2 gr (2 gr. 10 40 300 6 4 86 9 1 0 0 (2 gr (2 gr. 40 300 22. 2 6 90 3 1 0 0 (2 gr (2 gr. 10 40 300 8 76 10 6 0 0 (2 gr (2 gr. 10 45 300 37. 8 5 90 3 2 0 0 (2 gr.) (2 gr. 15 40 300 28. 5 9 88 2 1 0 0 NOTE-C Methane; C22 C211 CgHo; Cal C3H0 CaHs; C 04H: CAHIO; C5: CsHn- EXAMPLE 2 The procedures in Example 1 were repeated using two or three alkali metals, tungsten chloride and graphite to prepare a catalyst with which a mixture of hydrogen and carbon monoxide was contacted, the surface area of the catalyst being about 20 mP/g. The reaction conditions and results are given in Table 2.

25 reactor containing the catalyst at a rate of 15 cc./rnrn. Hy-

TABLE 2 Partial Amount pressure of hydroof gas carbons Proportlon of hydrocarbons (cm. Hg) Reaction produced (molar percent) mp. after 20 Catalyst 00 Hz C.) hrs. (00.) C1 C2 C3 C4 C5 K(2 gr.)-G(2 gr.) 10 300 1. 2 2 24 22 2 0 WOlo(0.2 gr.)-G(2 gr.) 10 40 300 0 WC16(1.0 gr.;-K(2 gr.)-G(2 gr.) 10 40 300 20 4 82 8 4 1 WC1(0.2 gr. -Na(2 gr.)-G- 10 40 300 38 12 80 6 2 1 WClu(0.2 gr.)-Rb(1 g'r.)-G(1 gr.) 10 40 300 18 2 87 8 2 2 Norn.-G=Graphlte.

EXAMPLE 3 drocarbons entrapped in cooler were subjected to gas chro- The catalysts prepared in Example 1 were used and 40 various mixtures of hydrogen, carbon monoxide and air or nitrogen were converted into ammonia and hydrocarbons.

matography and infrared analysis.

When 10-20 cm. Hg of oxygen was present in the synthesis gas, the catalytic activity did not decrease.

The reaction conditions and the results are given in TABLE 4 Partial pressure Amount of gas of hydro- Proportion of hydrocarbons (cm. Hg.) Reaction Reaction carbons (molar percent) temp. time produced Catalyst 00 Hz C.) (inn) (cc.) 0; Ca Ca 0 0 G (2 gr.)-K (2 gr.) 10 40 300 20 l. 2 2 74 22 2 0 C001; (1 gr.)-G (2 gr.)-K (2 gr 30 30 300 22 49. 8 5 91 3 1 0 The results are given in Table 3 from which it is observed that the presence of nitrogen and air does not Table 4 which also includes a two-component catalyst of graphite and metallic potassium for comparison.

adversely affect the formation of hydrocarbons.

TABLE 3 Amount of product after Reaction 20 hrs. (00.)

temper- Partlal pressure of ature Hydro- Catalyst gas (cm. Hg) O.) NH: carbon FeCla(0.2 gr.)-G (2 gr.)-K (2 gr.). {Air, 10; CO, 10; Hz, 40 300 18 20 N 10; 00, 10; H2, 40 300 21 16 W01 (0.2 gr.)-G (2 gr.)-K (2 gr.) Air, 10; CO, 10; Hz, 40.-- 300 0. 01. 30

EXAMPLE 4 EXAMPLE 5 A three-component catalyst was prepared in a 300 cc. glass U-shaped reactor 'by heating graphite and cobalt chloride at 300 C. and under a pressure of 10" mm. Hg

According to the procedures of Example 4, an alkali metal, a transition metal halide and graphite were employed for preparing catalyst and a mixture of hydrogen and carbon monoxide was contacted with the catailgshlhe surface area of catalyst was about 20 mfi/g. The reaction conditions and the results are given in Table 5.

melting point of said alkali metal under a reduced pressure of less than 10- cm. Hg.

TABLE 5 Proportion of hydrocarbons (molar percent) Partial pressure Amount oi of gas (cm. Hg.) hydro- Reaction Reaction carbons temp. time produced Catalyst 0 H2 0.) (hr.) (012.)

RhC1a(0.6 gr.)-G(2 gr.)-K(2 gr.) 10 40 300 20 6 I1C15(0.5 gr.)-G(2 gt.)-K(2 gr.) 30 30 300 22. 7. 1 ReCla(0. 5 gr.)-G(2 gr.)-K(2 gr 30 30 270 24 9. 4 ZrCl (0.5 gr.)-G(2 gr.)-K(2 gr.) 29. 2 30. 8 300 6 8. 3 T101406 gr.)G(2 gr.)-Na(2 gr.) 30 30 300 6 8. 5

We claim:

1. In the synthesis of hydrocarbons by reaction of carbon monoxide and hydrogen in the presence of a catalyst, the improvement which comprises conducting said reaction at a temperature of from 250 C. 'to 400 C. in the presence of an electron donor-acceptor complex catalyst consisting essentially of (a) an alkali metal,

(b) graphite, and

(c) a chloride of a transition metal selected from the group consisting of Groups IVB, VB, VIB, VIIB and VII-I of the Periodic Table, and wherein the weight ratio of said chloride to graphite is a 0.001-10z1 and of said alkali metal to graphite and chloride is 0.1-1021.

2. The synthesis of Claim 1, wherein the weight ratio of said chloride to graphite is 0.01-1.0z1 and of said alkali metal to graphite and chloride is 0.5-1.0:1.

13. The synthesis of Claim 1, wherein the alkali metal is sodium, potassium or rubidium.

4. The synthesis of Claim 1, wherein said complex is formed by heating a mixture of graphite and said chloride at a temperature of from about 200 C. to 500 C. to form a graphite-chloride interlayer complex,

adding said alkali metal to said interlayer complex, and

heating the resulting mixture at a temperature above the heating the resulting mixture at a temperature above the melting point of said alkali metal in an inert gas atmosphere.

References Cited UNITED STATES PATENTS 2,692,274 10/1954 Kolbel et al. 260449.6 2,660,598 11/1953 Holfert 260449 1,909,442 5/1933 Williams 260-449 M 2,564,696 8/1951 Keith et al 260449.6

HOWARD T. MARS, Primary Examiner US. Cl. X.R. 

1. IN THE SYNTHESIS OF HYDROCARBON BY REACTION OF CARBON MONOXIDE AND HYDROGEN IN THE PRESENCE OF A CATALYST, THE IMPROVEMENT WHICH COMPRISES CONDUCTING SAID REACTION AT A TEMPERATURE OF FROM 250*. THE 400*C. IN THE PRESENCE OF AN ELECTRON DONOR-ACCEPTOR COMPLEX CATALYST CONSISTING ESSENTIALLY OF (A) AN ALKALI METAL, (B) GRAPHITE, AND (C) A CHLORIDE OF A TRANSITION METAL SELCTED FROM THE GROUP CONSISTING OF GROUPS IVB, VB, VIB, VIIB AND VIII OF THE PERIODIC TABLE, AND WHEREIN THE WEIGHT RATIO OF SAID CHLORIDE TO GRAPHITE IS A 0.001-10:1 AND OF SAID ALKALI METAL TO GRAPHITE AND CHLORIDE IS 0.1-10-1. 